Out of stock
SKU: JEPJ100F8-4280-5
UPC: 193564228963
MPN: J100F8-4280-5
The Piston Ring Set 4.285 Moly 1/16 1/16 3/16 (Part J100F8-4280-5) is a premium race-series piston ring kit engineered for high-performance eight-cylinder engines with a 4.280-inch bore specification. Designed for file-fit installation, this complete piston ring set combines plasma moly coating with ductile iron construction to deliver superior ring life and blowby control in demanding racing and high-output applications.
The ring configuration—1/16-inch top ring, 1/16-inch second ring, and 3/16-inch oil ring—follows race-proven proportions that balance sealing efficiency with minimal friction. Plasma moly coating reduces ring wear, extends ring groove life, and improves oil control during extended high-RPM operation. Standard tension specification ensures consistent sealing force across cylinder walls without excessive sidewall wear. File-fit rings demand precise honing and installation technique, making them the choice for builders who require exact bore-to-ring clearance control and maximum compression retention.
This kit serves serious engine builders and performance shops preparing eight-cylinder racing engines, forced-induction street engines, or high-displacement naturally aspirated builds where compression stability and ring reliability are non-negotiable. File-fit rings demand professional installation with proper honing equipment and clearance verification—this is not a bolt-on component for casual assembly. The moly-coated construction particularly benefits engines experiencing extended full-throttle operation, sustained high boost, or elevated peak cylinder pressures where standard cast-iron rings would experience accelerated wear.
Piston ring selection directly impacts compression ratio stability, oil consumption, and long-term engine durability. Oversized ring sets for worn or rebored cylinders require specific bore measurements to ensure correct ring gap and land clearance. This 4.285-inch specification fits engines bored to that exact size; verify your engine's final bore dimension before purchase to confirm compatibility.
WARNING ⚠️
You must be 18 or older to purchase shotgun or rifle ammunition and 21 or older to purchase handgun ammunition and firearms. Please reference our requirements for ammunition orders to "restricted" states HERE. Always make sure you use the correct ammunition for your firearms. Ammo cannot be shipped to a PO Box. Please reference state & local laws before making a firearm or ammunition purchase.
Purchasing a Firearm? Click HERE to see our firearm purchasing guide.
